[Modeling T2 high severe asthma using human induced pluripotent stem cells (hiPSC)]

Severe asthma patients with persistent airflow obstruction are characterized by functional obstruction due to mucus plugs containing mucins, fibrin, and eosinophil derived Charcot- Leyden crystals. The molecular mechanisms underlying this endotype are not clearly understood. Developing new models is crucial to respiratory research insofar as critical differences exist between human and rodent airway epithelium. We (and other teams) have shown that it is possible to reconstitute in vitro a complex and functional airway epithelium displaying all the features described in vivo from human-induced pluripotent stem cells (hiPSC). Our aim is to establish a human in vitro model of severe asthma that will recapitulate airway epithelium remodeling and mucus plugs.

Developmental coordination disorder subtypes in children: An unsupervised clustering

AIM

To identify subtypes of developmental coordination disorder (DCD) in children.

METHOD

Children with DCD diagnosed through comprehensive evaluation at Robert-Debré Children's University Hospital (Paris, France) were consecutively enrolled from February 2017 to March 2020. We performed an unsupervised hierarchical clustering based on principal component analysis using a large set of variables encompassing cognitive, motor, and visuospatial scores (Wechsler Intelligence Scale for Children, Fifth Edition; Developmental Neuropsychological Assessment, Second Edition; Movement Assessment Battery for Children, Second Edition).

RESULTS

One hundred and sixty-four children with DCD were enrolled (median age 10 years 3 months; male:female ratio 5.56:1). We identified distinct subgroups with mixed visuospatial and gestural disorders, or with pure gestural disorders that predominantly impaired either speed or precision. Associated neurodevelopmental disorders, such as attention-deficit/hyperactivity disorder, did not influence the results of the clustering. Importantly, we identified a subgroup of children with marked visuospatial impairment with the lowest scores in almost all of the evaluated domains, and the poorest school performance.

INTERPRETATION

The classification of DCD into distinct subgroups could be indicative of prognosis and provide critical information to guide patient management, taking into account the child's neuropsychological profile. Beyond this clinical interest, our findings also provide a relevant framework with homogeneous subgroups of patients for research on the pathogenesis of DCD.

WHAT THIS PAPER ADDS

Unsupervised hierarchical clustering identified four subgroups of children with developmental coordination disorder. Two subgroups had combined visuospatial/gestural difficulties, and two had pure gestural disorders. Severe visuospatial impairment was associated with poor performance in most domains including school. Difficulties in the gestural-only clusters were predominantly either gestural precision or speed.

Non-Motor Symptoms and Quality of Life in Patients with PRRT2-Related Paroxysmal Kinesigenic Dyskinesia

Background

Monoallelic pathogenic variants of PRRT2 often result in paroxysmal kinesigenic dyskinesia (PKD). Little is known about health-related quality of life (HrQoL), non-motor manifestations, self-esteem, and stigma in patients with PKD.

Objectives

We investigated non-motor symptoms and how they related to HrQoL in a genetically homogeneous group of PRRT2-PKD patients. We paid special attention to perceived stigmatization and self-esteem.

Methods

We prospectively enrolled 21 consecutive PKD patients with a pathogenic variant of PRRT2, and 21 healthy controls matched for age and sex. They were evaluated with dedicated standardized tests for non-motor symptoms, HrQoL, anxiety, depression, stigma, self-esteem, sleep, fatigue, pain, and psychological well-being.

Results

Patients reported an alteration of the physical aspects of HrQoL, regardless of the presence of residual paroxysmal episodes. Non-motor manifestations were frequent, and were an important determinant of the alteration of HrQoL. In addition, patients perceived a higher level of stigmatization which positively correlated with a delay in diagnosis (ρ = 0.615, P = 0.003) and the fear of being judged (ρ = 0.452, P = 0.04), but not with the presence of paroxysmal episodes (ρ = 0.203, P = 0.379).

Conclusions

Our findings have important implications for care givers concerning patient management and medical education about paroxysmal dyskinesia. PRRT2-PKD patients should be screened for non-motor disorders in routine care. A long history of misdiagnosis may play a role in the high level of perceived stigmatization. Improving knowledge about diagnostic clues suggestive of PKD is mandatory.

Prospective Multicenter Validation of a Simple Blood Test for the Diagnosis of Glut1 Deficiency Syndrome

BACKGROUND AND OBJECTIVE

GLUT1 deficiency syndrome (Glut1DS) is a treatable neurometabolic disease that causes a wide range of neurologic symptoms in children and adults. However, its diagnosis relies on an invasive test, that is, a lumbar puncture (LP) to measure glycorrhachia, and sometimes complex molecular analyses of the SLC2A1 gene. This procedure limits the number of patients able to receive the standard of care. We wished to validate the diagnostic performance of METAglut1, a simple blood test that quantifies GLUT1 on the erythrocyte surface.

METHODS

We performed a multicenter validation study in France, involving 33 centers. We studied 2 patient cohorts: a prospective cohort consisting of patients with a clinical suspicion of Glut1DS explored through the reference strategy, that is, LP and analyses of the SLC2A1 gene, and a retrospective cohort that included patients previously diagnosed with Glut1DS. All patients were blind-tested with METAglut1.

RESULTS

We analyzed 428 patients in the prospective cohort, including 15 patients newly diagnosed with Glut1DS, and 67 patients in the retrospective cohort. METAglut1 was 80% sensitive and >99% specific for the diagnosis of Glut1DS. Concordance analyses showed a substantial agreement between METAglut1 and glycorrhachia. In the prospective cohort, the positive predictive value of METAglut1 was slightly higher than that of glycorrhachia. METAglut1 succeeded to identify patients with Glut1DS with SCL2A1 mosaicism and variants of unknown significance.

DISCUSSION

METAglut1 is an easily performed, robust, and noninvasive diagnostic test for the diagnosis of Glut1DS, which allows wide screening of children and adults, including those with atypical forms of this treatable condition.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that a positive METAglut1 test accurately distinguishes patients with suspected GLUT1 deficiency syndrome from other neurologic syndromes as compared with invasive and genetic testing.

Intraputaminal Gene Delivery in Two Patients with Aromatic L-Amino Acid Decarboxylase Deficiency

BACKGROUND

Aromatic l-amino acid decarboxylase deficiency (AADCD) is a rare, early-onset, dyskinetic encephalopathy mostly reflecting a defective synthesis of brain dopamine and serotonin. Intracerebral gene delivery (GD) provided a significant improvement among AADCD patients (mean age, ≤6 years).

OBJECTIVE

We describe the clinical, biological, and imaging evolution of two AADCD patients ages >10 years after GD.

METHODS

Eladocagene exuparvovec, a recombinant adeno-associated virus containing the human complimentary DNA encoding the AADC enzyme, was administered into bilateral putamen by stereotactic surgery.

RESULTS

Eighteen months after GD, patients showed improvement in motor, cognitive and behavioral function, and in quality of life. Cerebral l-6-[18F] fluoro-3, 4-dihydroxyphenylalanine uptake was increased at 1 month, persisting at 1 year compared to baseline.

CONCLUSION

Two patients with a severe form of AADCD had an objective motor and non-motor benefit from eladocagene exuparvovec injection even when treated after the age of 10 years, as in the seminal study.

A recurrent de novo splice site variant involving DNM1 exon 10a causes developmental and epileptic encephalopathy through a dominant-negative mechanism

Heterozygous pathogenic variants in DNM1 cause developmental and epileptic encephalopathy (DEE) as a result of a dominant-negative mechanism impeding vesicular fission. Thus far, pathogenic variants in DNM1 have been studied with a canonical transcript that includes the alternatively spliced exon 10b. However, after performing RNA sequencing in 39 pediatric brain samples, we find the primary transcript expressed in the brain includes the downstream exon 10a instead. Using this information, we evaluated genotype-phenotype correlations of variants affecting exon 10a and identified a cohort of eleven previously unreported individuals. Eight individuals harbor a recurrent de novo splice site variant, c.1197-8G>A (GenBank: NM_001288739.1), which affects exon 10a and leads to DEE consistent with the classical DNM1 phenotype. We find this splice site variant leads to disease through an unexpected dominant-negative mechanism. Functional testing reveals an in-frame upstream splice acceptor causing insertion of two amino acids predicted to impair oligomerization-dependent activity. This is supported by neuropathological samples showing accumulation of enlarged synaptic vesicles adherent to the plasma membrane consistent with impaired vesicular fission. Two additional individuals with missense variants affecting exon 10a, p.Arg399Trp and p.Gly401Asp, had a similar DEE phenotype. In contrast, one individual with a missense variant affecting exon 10b, p.Pro405Leu, which is less expressed in the brain, had a correspondingly less severe presentation. Thus, we implicate variants affecting exon 10a as causing the severe DEE typically associated with DNM1-related disorders. We highlight the importance of considering relevant isoforms for disease-causing variants as well as the possibility of splice site variants acting through a dominant-negative mechanism.

Evaluation of a multisensory algorithm to prevent acute decompensation of heart failure in patients implanted with a cardioverter defibrillator: rationale and design

Background

Heart failure (HF) is a chronic disease affecting 64 million people worldwide and places a severe burden on society because of its mortality, numerous re-hospitalizations and associated costs [1–4]. HeartLogic is an algorithm incorporating several biometric parameters which aims to predict HF episodes. It provides an index which can be monitored remotely, allowing preemptive treatment of congestion to prevent acute decompensation [5–7].

Objectives

We aim to provide real-world data on the impact of pre-emptive HF management, guided by the HeartLogic index on unscheduled HF hospitalizations in a substantial cohort of patients.

Methods

The HeartLogic French Study is an investigator-initiated, prospective, multi-centre, non-randomized study. All in all, 310 patients with a history of HF (left ventricular ejection fraction ≤40%; or at least one episode of clinical HF with elevated NT-proBNP ≥450 ng/L) and implanted with a cardioverter defibrillator enabling HeartLogic index calculation will be included across 10 French centers. The HeartLogic index will be monitored remotely on a weekly basis for 12 months and in case of HeartLogic index ≥16, the local investigator will contact the patient for assessment and adjust HF treatment as necessary. The primary endpoint is unscheduled hospitalization for HF. Secondary endpoints are all-cause mortality, cardiovascular death, HF-related death, and unscheduled hospitalizations for ventricular or atrial arrhythmia. Blood samples will be collected for biobanking, and quality of life will be assessed. A blind and independent committee will adjudicate the events.

Conclusions

The HeartLogic French Cohort Study will provide robust real-world data on HF hospitalization in a cohort of patients managed with the HeartLogic algorithm allowing preemptive treatment of congestion.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Boston Scientific

Low voltage area as a predictor of recurrence after a single pulmonary vein isolation procedure: results of the WAVE-MAP AF study

Background/Introduction

Pulmonary vein isolation (PVI) is a recommended approach for atrial fibrillation (AF) ablation procedures. Substrate modification beyond PVI has mixed results but identifying and ablating low voltage zones and ablating those targets in addition to PVI may be beneficial. Electroanatomic mapping is critical to identify subjects that may require further substrate modification. Low voltage area may be predictive of optimal treatment approach.

Purpose

This was a prospective, multicenter, interventional study of a high-density grid-style mapping catheter (HD Grid) to characterize left atrial low voltage substrate during sinus rhythm (SR) and AF and identify associations with 12 month recurrence rates after a single de novo radiofrequency (RF) ablation using a PVI only approach.

Methods

This study (NCT03882021) enrolled 300 subjects at 18 centers in Europe and Israel. Subjects underwent de novo RF ablation for paroxysmal AF (PAF) (N=113), early persistent AF (PsAF; AF sustained 7 days to 3 months) (N=86) or non-early PsAF (AF sustained >3 months to 12 months) (N=101). High density voltage maps were collected with HD Grid. Two pre-ablation maps, in SR and AF, were created for each subject (N=196) followed by PVI only ablation. Low voltage area (using cutoffs of 0.1 mV to 1.5 mV) was investigated in SR and AF. Follow up visits were at 3, 6 and 12 months post-ablation, with a 24-hour Holter monitor at 12 months. A Cox proportional hazards model was used to identify associations between mapping data and 12 month AF/atrial flutter (AFL)/atrial tachycardia (AT) recurrence after a single PVI procedure.

Results

At 12 months, 75.5% of subjects were free from AF/AFL/AT recurrence. On average, PsAF subjects had more low voltage area than PAF subjects in SR and AF. However, while univariate analysis found no correlation between recurrence and PAF or PsAF diagnosis (p=0.1261), those with recurrence had a significantly larger percent left atrial low voltage area under 0.5 mV with simultaneous orthogonal bipole wave configuration (HDW) in both AF (p=0.0011) and SR (p=0.0210) than those without recurrence. Using HDW, low voltage area (identified as <0.5 mV) greater than 28% of the left atrium in SR (HR: 4.82, 95% CI: 2.08–11.18, p=0.0003) and greater than 72% in AF (HR: 5.66, 95% CI: 2.34–13.69, p=0.0001) were associated with a higher risk of AF/AFL/AT recurrence at one year.

Conclusion(s)

Using a standard cutoff of 0.5 mV, a larger percent low voltage area was associated with increased risk of recurrence in both SR and AF. Future analyses will explore optimal low voltage cutoffs and thresholds predictive of recurrence that may necessitate additional substrate modification beyond PVI.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Abbott

Strategic management to optimize response to cardiac resynchronization therapy registry

Background

Cardiac resynchronization therapy (CRT) is guideline-recommended for the treatment of symptomatic heart failure (HF) in patients (pts) with reduced LVEF and prolonged QRS. Clinical trials report Clinical Composite Score (CCS) response rates from 60 to 75%. However, patients with common comorbidities, such as atrial fibrillation, are often under-represented in clinical trials. The Strategic MAnagement to optimize response to cardiac Resynchronization Therapy (SMART) Registry (NCT03075215) was designed to examine outcomes in CRT patients in the real world.

Methods

The SMART Registry was a global, multicenter, prospective, clinical registry that enrolled subjects undergoing a de novo CRT-D implant or upgrade from pacemaker to CRT-D using a quadripolar LV lead. CCS was assessed at 12 months post-implant.

Results

For study design and CCS outcomes see Figure 1. CCS at 12 months showed that 58.8% of pts improved and 20.1% stabilized. Of the 21.1% of pts that worsened, 8.4% were due to death, 7.8% non-fatal heart failure event, and 5% worsening of NYHA or patient global assessment. Notably, this registry had a high prevalence of pts with NYHA I/II (51%), Non-LBBB (50%), AF (37%), diabetes (35%), and bradycardia (31%) at baseline. Age (>65), diabetes, ischemia, non-LBBB, atrial fibrillation (AF) and renal dysfunction correlated with worsened CCS outcomes. NYHA III/IV patients had significantly higher HF hospitalization (HFH) rates than NYHA I/II (P-value <0.001) (Figure 2a) and patients with AF had higher HFH rates than those without (P-value <0.001) (Figure 2b). Similar effects of NYHA score and AF were seen on mortality. The use of ACE/ARB, or ARNI, and MRA correlated with better outcomes, whereas diuretics and anticoagulants correlated with poorer outcomes.

Conclusions

In this large registry, clinical outcomes across important sub-populations are in line with expectations, with older age, ischemia, renal dysfunction, AF, non-LBBB, and diabetes associated with a lower likelihood of response to CRT. By including these patients, this study provides a clearer picture of the effectiveness of CRT in the real world. Future studies should examine optimization approaches to facilitate CRT effectiveness in these under studied patient populations.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): This registry was funded by Boston Scientific (BSC)

High density wave mapping to characterize low voltage substrate in sinus rhythm and atrial fibrillation: acute results from the WAVE-MAP AF study

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Abbott

Background

Pulmonary vein isolation (PVI) is a recommended approach for all atrial fibrillation (AF) ablation procedures, but PVI alone does not cure all AF. Supplementary substrate modification beyond PVI has mixed results. Identifying low voltage zones and ablating those targets in addition to PVI may be beneficial. Electroanatomic mapping is critical to identify subjects that may require further substrate modification. The amount of low voltage area may be predictive of the optimal treatment approach.

Purpose

This was a prospective, multicenter, interventional study of a high-density grid-style mapping catheter (HD Grid) to characterize left atrial (LA) low voltage substrate during sinus rhythm (SR) and AF in subjects undergoing de novo radiofrequency (RF) ablation for paroxysmal AF (PAF), early persistent AF (PsAF) (7 days-3 months) or non-early PsAF (>3 months-12 months) using a PVI only approach.

Methods

High-density voltage maps were collected with HD Grid during both SR and AF prior to ablation. Differences in low voltage area between (1) SR and AF and (2) simultaneous orthogonal bipole wave configuration (HDW) and standard along-the-spline linear electrode configuration (SD) were investigated.

Results

Three hundred subjects, enrolled at 18 centers in Europe and Israel, underwent PVI only RF ablation for PAF (N=113), early PsAF (N=79), and non-early PsAF (N=108). The average age was 62.0 ± 9.5 years and 70.3% (211/300) were male. SR maps and AF maps were available and evaluated in HDW and SD for 196 subjects (65.3%) (63 PAF, 65 early PsAF, 68 non-early PsAF). Mean LA surface area was 108.8 cm² and mean mapped surface area ranged from 83.2 to 89.5 cm².

HDW maps showed less low voltage area compared to SD in all subgroups, both in AF and in SR (Figure). For example, in AF with a low voltage cutoff of 0.5 mV, mean low voltage area was 49.8 cm² using SD and only 45.6 cm² using HDW (p<.0001). Similarly, in SR with a low voltage cutoff of 0.5 mV, mean low voltage area was 16.1 cm² using SD and only 12.6 cm² using HDW (p<.0001). HDW showed significantly less low voltage area than SD in SR for all measured voltage cutoffs from 0.1 mV to 1.5 mV.

On average, non-early PsAF subjects had a larger low voltage area than early PsAF subjects and PAF subjects in both SR and AF. In SR HDW, non-early PsAF subjects had 15.6 cm² under 0.5 mV, early PsAF subjects had 12.4 cm², and PAF subjects had 9.2 cm² (p=.0316). In AF HDW, non-early PsAF subjects had 56.6 cm² under 0.5 mV, early PsAF had 42.8 cm² and PAF subjects had 35.4 cm² (p<.0001).

Conclusion

Non-early PsAF subjects had the largest low voltage area on average compared to both early PsAF and PAF subjects in this study. Using HD grid, HDW provided better low voltage area characterization compared to SD in both SR and AF. The final results of this study will suggest whether an HDW substrate characterization of low voltage area can predict recurrences after a single PVI-only strategy procedure.

Efficacy of Caffeine in ADCY5-Related Dyskinesia: A Retrospective Study

BACKGROUND

ADCY5-related dyskinesia is characterized by early-onset movement disorders. There is currently no validated treatment, but anecdotal clinical reports and biological hypotheses suggest efficacy of caffeine.

OBJECTIVE

The aim is to obtain further insight into the efficacy and safety of caffeine in patients with ADCY5-related dyskinesia.

METHODS

A retrospective study was conducted worldwide in 30 patients with a proven ADCY5 mutation who had tried or were taking caffeine for dyskinesia. Disease characteristics and treatment responses were assessed through a questionnaire.

RESULTS

Caffeine was overall well tolerated, even in children, and 87% of patients reported a clear improvement. Caffeine reduced the frequency and duration of paroxysmal movement disorders but also improved baseline movement disorders and some other motor and nonmotor features, with consistent quality-of-life improvement. Three patients reported worsening.

CONCLUSION

Our findings suggest that caffeine should be considered as a first-line therapeutic option in ADCY5-related dyskinesia. © 2022 International Parkinson and Movement Disorder Society.

Cerebellum Dysfunction in Patients With PRRT2-Related Paroxysmal Dyskinesia

Background and Objectives:

The main culprit gene for paroxysmal kinesigenic dyskinesia, characterized by brief and recurrent attacks of involuntary movements, is PRRT2. The location of the primary dysfunction associated with paroxysmal dyskinesia remains a matter of debate and may vary depending on the etiology. While striatal dysfunction has often been implicated in these patients, evidence from preclinical models indicate that the cerebellum could also play a role. We aimed to investigate the role of the cerebellum in the pathogenesis of PRRT2-related dyskinesia in humans.

Methods:

We enrolled 22 consecutive right-handed patients with paroxysmal kinesigenic dyskinesia with a pathogenic variant of PRRT2, and their matched controls. Participants underwent a multi-modal neuroimaging protocol. We recorded anatomic and diffusion-weighted MRI, as well as resting-state functional MRI during which we tested the after-effects of sham and repetitive transcranial magnetic stimulation applied to the cerebellum on endogenous brain activity. We quantified: (i) the structural integrity of gray matter using voxel-based morphometry; (ii) the structural integrity of white matter using fixel-based analysis; (iii) the strength and direction of functional cerebellar connections using spectral dynamic causal modeling.

Results:

PRRT2 patients had: (i) decreased gray matter volume in the cerebellar lobule VI and in the medial prefrontal cortex; (ii) microstructural alterations of white matter in the cerebellum and along the tracts connecting the cerebellum to the striatum and the cortical motor areas; (iii) dysfunction of cerebellar motor pathways to the striatum and the cortical motor areas, as well as abnormal communication between the associative cerebellum (Crus I) and the medial prefrontal cortex. Cerebellar stimulation modulated communication within the motor and associative cerebellar networks, and tended to restore this communication to the level observed in healthy controls.

Discussion:

Patients with PRRT2-related dyskinesia have converging structural alterations of the motor cerebellum and related pathways with a dysfunction of cerebellar output towards the cerebello-thalamo-striato-cortical network. We hypothesize that abnormal cerebellar output is the primary dysfunction in patients with a PRRT2 pathogenic variant, resulting in striatal dysregulation and paroxysmal dyskinesia. More broadly, striatal dysfunction in paroxysmal dyskinesia might be secondary to aberrant cerebellar output transmitted by thalamic relays in certain disorders.

Clinical trial number:

NCT03481491 (https://ichgcp.net/clinical-trials-registry/NCT03481491)

Opsoclonus-myoclonus in Aicardi-Goutières syndrome

Aicardi-Goutières syndrome (AGS) is a rare genetic neuroinflammatory disorder caused by abnormal upregulation of type 1 interferon signalling. Opsoclonus-myoclonus syndrome is a rare autoimmune phenotype demonstrating a disturbance in the humoral immune response mostly seen in the context of paraneoplastic or postinfectious states, although its pathophysiology is incompletely understood. We report the first three children described with AGS demonstrating transient opsoclonus and myoclonus after irritability and/or developmental regression, suggesting a pathological association. We describe the presentation, clinical features, progress, cerebrospinal fluid (CSF) inflammatory markers, electroencephalogram (EEG), and magnetic resonance imaging (MRI) findings in these children. Two patients had developmental regression but demonstrated a positive response to JAK1/2 inhibition clinically and on serial examination of CSF inflammatory markers. These findings suggest that AGS should be considered in children presenting with opsoclonus-myoclonus, and that the association between AGS and opsoclonus-myoclonus further supports the role of immune dysregulation as causal in the rare neurological phenomenon opsoclonus and myoclonus. What this paper adds There is a phenotypic association between opsoclonus-myoclonus syndrome and Aicardi-Goutières syndrome. There is clinical evidence of immune dysregulation in the pathogenesis of opsoclonus and myoclonus.

GM3 synthase deficiency in non-Amish patients

PURPOSE

Biallelic loss-of-function variants in ST3GAL5 cause GM3 synthase deficiency (GM3SD) responsible for Amish infantile epilepsy syndrome. All Amish patients carry the homozygous p.(Arg288Ter) variant arising from a founder effect. To date only 10 patients from 4 non-Amish families have been reported. Thus, the phenotypical spectrum of GM3SD due to other variants and other genetic backgrounds is still poorly known.

METHODS

We collected clinical and molecular data from 16 non-Amish patients with pathogenic ST3GAL5 variants resulting in GM3SD.

RESULTS

We identified 12 families originating from Reunion Island, Ivory Coast, Italy, and Algeria and carrying 6 ST3GAL5 variants, 5 of which were novel. Genealogical investigations and/or haplotype analyses showed that 3 of these variants were founder alleles. Glycosphingolipids quantification in patients' plasma confirmed the pathogenicity of 4 novel variants. All patients (N = 16), aged 2 to 12 years, had severe to profound intellectual disability, 14 of 16 had a hyperkinetic movement disorder, 11 of 16 had epilepsy and 9 of 16 had microcephaly. Other main features were progressive skin pigmentation anomalies, optic atrophy or pale papillae, and hearing loss.

CONCLUSION

The phenotype of non-Amish patients with GM3SD is similar to the Amish infantile epilepsy syndrome, which suggests that GM3SD is associated with a narrow and severe clinical spectrum.

Joint Position Paper of the Working Group of Pacing and Electrophysiology of the French Society of Cardiology (SFC) and the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV) on magnetic resonance imaging in patients with cardiac electronic implantable devices

Magnetic resonance imaging (MRI) has become the reference imaging for the management of a large number of diseases. The number of MR examinations increases every year, simultaneously with the number of patients receiving a cardiac electronic implantable device (CEID). A CEID was considered an absolute contraindication for MRI for years. The progressive replacement of conventional pacemakers and defibrillators by MR-conditional CEIDs and recent data on the safety of MRI in patients with "MR-nonconditional" CEIDs have progressively increased the demand for MRI in patients with a CEID. However, some risks are associated with MRI in CEID carriers, even with "MR-conditional" devices because these devices are not "MR-safe". A specific programing of the device in "MR-mode" and monitoring patients during MRI remain mandatory for all patients with a CEID. A standardized patient workflow based on an institutional protocol should be established in each institution performing such examinations. This joint position paper of the Working Group of Pacing and Electrophysiology of the French Society of Cardiology and the Société française d'imagerie cardiaque et vasculaire diagnostique et interventionnelle (SFICV) describes the effect and risks associated with MRI in CEID carriers. We propose recommendations for patient workflow and monitoring and CEID programming in MR-conditional, "MR-conditional nonguaranteed" and MR-nonconditional devices.

Early-onset nucleotide excision repair disorders with neurological impairment: Clues for early diagnosis and prognostic counseling

Nucleotide excision repair associated diseases comprise overlapping phenotypes and a wide range of outcomes. The early stages still remain under-investigated and underdiagnosed, even although an early recognition of the first symptoms is of utmost importance for appropriate care and genetic counseling. We systematically collected clinical and molecular data from the literature and from newly diagnosed NER patients with neurological impairment, presenting clinical symptoms before the age of 12 months, including foetal cases. One hundred and eighty-five patients were included, 13 with specific symptoms during foetal life. Arthrogryposis, microcephaly, cataracts, and skin anomalies are the most frequently reported signs in early subtypes. Non ERCC6/CSB or ERCC8/CSA genes are overrepresented compared to later onset cohorts: 19% patients of this cohort presented variants in ERCC1, ERCC2/XPD, ERCC3/XPB or ERCC5/XPG. ERCC5/XPG is even the most frequently involved gene in foetal cases (10/13 cases, [4/7 families]). In this cohort, the mutated gene, the age of onset, the type of disease, severe global developmental delay, IUGR and skin anomalies were associated with earlier death. This large survey focuses on specific symptoms that should attract the attention of clinicians towards early-onset NER diagnosis in foetal and neonatal period, without waiting for the completeness of classical criteria.

[Movement disorders in children]

Movement disorders in children. The phenomenological spectrum of pediatric movement disorders is wide and correspond to a large variety of causes. It comprises fixed transient, and progressive disorders. Relative frequencies differ from those observed in adult neurology. Neurodevelopmental motor disorders such as tics, stereotypies and dystonia are more prevalent than parkinsonism. Proper characterization of the movement disorder is the starting point to the diagnosis. A particular attention should be paid to detailed clinical history, associated features, psychomotor development, tempo of appearance and time course of symptoms, precipitating or alleviating factors, and interference with voluntary movements. Evaluation of the functional impairment is critical to guide the clinical care of the children. Focus on potentially treatable disorders is essential. Here, we propose some practical guidance for diagnosis and treatment of movement disorders in children.

P999Major adverse events with percutaneous left atrial appendage closure in patients with atrial fibrillation in real life setting

Methods

We analysed data from all AF patients treated with Watchman or Amplatzer LAA closure according to European guidelines in 8 French cardiology departments. Antithrombotic management was decided for each patient on an individual basis. A Cox regression model was used for multivariable analysis of major adverse events. Yearly rate of ischemic stroke during follow-up was calculated and compared to that expected for a same risk score population. Yearly rate of bleeding was extrapolated from that reported with the HASBLED score.

Results

A total of 469 consecutive AF patients (299 males, 74.9±8.9 years old, mean CHA2DS2-VASc score 4.5±1.4, HASBLED score 3.7±1.0) received LAA closure from March 2012 to January 2017. There were 272 Watchman devices (58%) and 197 ACP devices (42%) implanted. At discharge, 36% received a single anti platelet therapy (APT), 23% received dual APT, 29% received OAC and no APT, 5% received OAC plus APT and 8% received no antithrombotic therapy. Mean follow up was 11.4 months (median 7, interquartile 3–22 months) during which 70 major adverse events (19 ischemic strokes, 18 major haemorrhages and 33 deaths) were recorded in 69 patients. The annual rate of ischemic stroke was 3.96%, which translates into a 13% relative risk reduction (95% CI −59 to 52%) as compared with the calculated stroke rate for similar CHA2DS2-VASc score after adjustment for exposure to APT and OAC. The annual rate of major bleeding in the study was 3.75%, which corresponds to a 48% relative risk reduction (95% CI 9 to 70%) as compared with the rate that would have been expected based on a comparable HAS-BLED score. Yearly rate of mortality was 7.4% (2.5 to 3 fold higher than in previous randomized trials) and the rate of non-cardiovascular death was 82%. None of the baseline characteristics was predictive of major adverse events, neither in univariate nor in multivariable analysis, which highlights the difficulty in identifying a risk of unfavourable outcome with simple tools.

Conclusions

AF patients treated with LAA closure may have a lower risk of stroke and bleeding events compared to their theoretical risk. However, our findings indicate that a high rate of major adverse events is observed in these patients during follow-up. This questions the suggested cost-effectiveness of the procedure (with models based on previous trials) for a real-life perspective. A better identification of patients with a relevant benefit of LAA closure is needed among those with long-term anticoagulation contraindication, both for an optimal management of each patient on an individual basis and for a global perspective with limited healthcare resources.

P5687CRT-D device replacement strategy according to previous ventricular tachycardia events: Preliminary Results of the BioCONTINUE Study

Background

The need for ICD back-up may be questionable in candidates for CRT-D device replacement, who no longer meet ICD criteria due to an improved left ventricular ejection fraction (LVEF) and/or an event-free CRT-D service life.

Purpose

To evaluate the clinical relevance of ICD back-up after CRT-D device replacement in patients with primary prevention ICD indication and to investigate factors predictive of ventricular arrhythmic events (VAE).

Methods

BioCONTINUE is an observational, multicentre, prospective and international trial. Patients were enrolled after CRT-D replacement and are currently followed up to a minimum of 2 years. We investigated the rate of patients with at least 1 sustained VAE, as defined by ventricular tachycardia >30s and/or ventricular arrhythmic event treated either by ATP or shock. Predictive factors of VAE were evaluated using univariate analyses based on demographics and clinical variables observed at enrolment, followed by a multivariate analysis. These multivariate analyses were adjusted confusion demographic or clinical covariates emerging at a p<0.2 level of significance by single variable analysis.

Results

A total of 276 patients are enrolled (70±10 years, 77% men, mean LVEF 40.6±12.6%, 23.6% secondary ICD indication). The mean FU duration at the interim analysis is 19.8±8.7 months, including 98 patients (35.5%) with a 2-year FU. The rate of patients free of VAE, is 91.2%, 88.4% and 85.1% respectively at 1, 2 and 3 years of FU. In patients with persistent ICD indication at enrolment (defined by LVEF <40% and/or previous VAE), the risk of VAE after device replacement is 3.3 times higher (95% CI: 1.4–8.2; p=0.007) than patients with no persistent ICD indication. The risk of VAE remains in patients with no persistent ICD indication, with a rate of 4.9% (95% CI 1.8%-10.4%). On multivariate analysis, age, ICD indication and ischemic heart disease, predicted VAE after the device replacement, with HR 0.96 (95% CI: 0.92–0.99; p=0.02), HR 3.01 (95% CI: 1.21–7.46; p=0.02) and HR 3.60 (95% CI: 1.54–8.42; p=0.003) respectively.

Conclusions

The interim results of the BioCONTINUE trial show a persistent risk of VAE after CRT-D device replacement, both in patients with and without persistent ICD indication. The risk of VAE is dependent on age, ICD indication and ischemic heart disease.

Acknowledgement/Funding

Supported by Biotronik

2404The use of wearable cardioverter defibrillator in France

Background

The wearable cardioverter defibrillator (WCD) has been shown to be useful during transient periods of high sudden cardiac death risk, and the issue of compliance recently pointed out. This Registry was designed to provide real-world data on WCD use in France, in terms of compliance, potential adverse events, as well as efficacy.

Methods and results

Multicenter evaluation (WEARIT FRANCE Registry) was conducted in France between January 2017 and March 2018. Overall, 1,157 patients were analyzed: 950 with ischemic heart disease (82%, including 647 patients after myocardial infarction), 119 after ICD explant (10%), and 88 pre-transplant (8%). The median age was 61 years; the median ejection fraction was 25%. Median WCD wear time was 62 days, with median daily use of 23.4 hours. Less than 1% of patients did not wear WCD at least 4 hours per day. During follow-up, a total of 42 sustained ventricular tachyarrhythmias (VT/VF) occurred in 36 patients, of whom 50% (n=18) received appropriate WCD shocks, giving an incidence of appropriate therapy of 1.56%. The rate of all VT/VF episodes were 3.1% among patients with ischemic cardiomyopathy (n=29/950) versus 3.4% for the others (n=7/207). Of the ischemic patients wearing beyond 30 days (N=784), 5 received appropriate therapy of VT/VF episodes. Overall shock survival was 100%. At the end of the WCD period, 586 patients (51%) were implanted with an implantable cardioverter defibrillator. Eight patients (0.69%) received inappropriate WCD shocks. Regarding the apparent very low proportion of women considered for WCD therapy, we aimed to appreciate in which extent

Conclusions

In this multicenter nationwide WCD evaluation, 3.1% of patients presented with sustained VT/VF with 47% of those patients developing VT/VF after 30 days. The incidence of inappropriate therapy was low. The compliance to WCD in this real life evaluation was very high. These data suggest that the WCD, when worn appropriately, may be helpful in the arsenal to protect high-risk patients against SCD, especially in case of transient risk situations.

Acknowledgement/Funding

Zoll

Cypress pollen allergy is responsible for two distinct phenotypes of allergic rhinitis different from other pollinosis

Summary

Different phenotypes of allergic rhinitis have been identified based on the seasonality of the allergen involved. Within pollinosis, importance has to be paid to the responsible pollen species. Guidelines for clinical management are mostly based on studies performed in patients with grass pollen allergy. Only few data is available on tree pollen allergy and more specifically on cypress pollen allergy. We focused on the clinical and biological features of cypress pollen allergy to determine whether it is associated with a specific phenotype of allergic rhinitis or not. Our results suggest that cypress pollen can be responsible for two distinct phenotypes of rhinitis, both different from other pollinosis. In the most common phenotype, cypress pollen was not responsible for bronchial hyperresponsiveness or systemic inflammation. Close attention has to be paid to the allergen involved in allergic rhinitis. Different phenotypes leading to different pharmacological strategies may apply.

Social cognition in autism is associated with the neurodevelopment of the posterior superior temporal sulcus

OBJECTIVE

The posterior superior temporal sulcus (pSTS) plays a critical role in the 'social brain'. Its neurodevelopment and relationship with the social impairment in autism spectrum disorders (ASD) are not well understood. We explored the relationship between social cognition and the neurodevelopment of the pSTS in ASD.

METHOD

We included 44 adults with high-functioning ASD and 36 controls. We assessed their performances on the 'Reading the mind in the eyes' test (for 34 of 44 subjects with ASD and 30 of 36 controls), their fixation time on the eyes with eye tracking (for 35 of 44 subjects with ASD and 30 of 36 controls) and the morphology of the caudal branches of the pSTS (length and depth), markers of the neurodevelopment, with structural MRI.

RESULTS

The right anterior caudal ramus of the pSTS was significantly longer in patients with ASD compared with controls (52.6 mm vs. 38.3 mm; P = 1.4 × 10^-3 ; Cohen's d = 0.76). Its length negatively correlated with fixation time on the eyes (P = 0.03) in the ASD group and with the 'Reading the mind in the eyes' test scores in both groups (P = 0.03).

CONCLUSION

Our findings suggest that the neurodevelopment of the pSTS is related to the ASD social impairments.

A simple blood test expedites the diagnosis of glucose transporter type 1 deficiency syndrome

Glucose transporter type 1 (GLUT1) deficiency syndrome (GLUT1‐DS) leads to a wide range of neurological symptoms. Ketogenic diets are very efficient to control epilepsy and movement disorders. We tested a novel simple and rapid blood test in 30 patients with GLUT1‐DS with predominant movement disorders, 18 patients with movement disorders attributed to other genetic defects, and 346 healthy controls. We detected significantly reduced GLUT1 expression only on red blood cells from patients with GLUT1‐DS (23 patients; 78%), including patients with inconclusive genetic analysis. This test opens perspectives for the screening of GLUT1‐DS in children and adults with cognitive impairment, movement disorder, or epilepsy. Ann Neurol 2017;82:133–138

Use of modified Atkins diet in glucose transporter type 1 deficiency syndrome

AIM

Glucose transporter type 1 deficiency syndrome (GLUT1-DS) results from impaired glucose transport into the brain, and is treated with a ketogenic diet. A few reports have suggested effectiveness of treatment using the modified Atkins diet (MAD). We aimed to assess the efficacy of MAD as a treatment for GLUT1-DS.

METHOD

We evaluated the efficacy of MAD in 10 patients (four males, six females; mean age at diagnosis [SD] 6.2y [1.7], min-max: 4mo-12y) with GLUT1-DS.

RESULTS

MAD was started at diagnosis in eight patients, including two infants. The mean duration (SD) under MAD was 2.5 [0.6] years (range 6mo-6y). Seven patients with epilepsy started MAD at GLUT1-DS diagnosis, and all experienced improvements in their epilepsy: five out of seven were seizure-free at M1, and three out of six at M3 and M6. The initiation of MAD allowed symptoms to be controlled in the three patients with movement disorders but without seizures. Two patients switched from the ketogenic diet to MAD. This switch was not responsible for the recurrence of any symptoms, and led to improvements in both physical abilities and growth parameters.

INTERPRETATION

MAD, which is a less restrictive and more palatable diet than the ketogenic diet, seems to have comparable effectiveness. Moreover, a switch from the ketogenic diet to MAD appears to be beneficial for patients with GLUT1-DS.

Triheptanoin dramatically reduces paroxysmal motor disorder in patients with GLUT1 deficiency

OBJECTIVE

On the basis of our previous work with triheptanoin, which provides key substrates to the Krebs cycle in the brain, we wished to assess its therapeutic effect in patients with glucose transporter type 1 deficiency syndrome (GLUT1-DS) who objected to or did not tolerate ketogenic diets.

METHODS

We performed an open-label pilot study with three phases of 2 months each (baseline, treatment and withdrawal) in eight patients with GLUT1-DS (7-47 years old) with non-epileptic paroxysmal manifestations. We used a comprehensive patient diary to record motor and non-motor paroxysmal events. Functional (31)P-NMR spectroscopy was performed to quantify phosphocreatine (PCr) and inorganic phosphate (Pi) within the occipital cortex during (activation) and after (recovery) a visual stimulus.

RESULTS

Patients with GLUT1-DS experienced a mean of 30.8 (± 27.7) paroxysmal manifestations (52% motor events) at baseline that dropped to 2.8 (± 2.9, 76% motor events) during the treatment phase (p = 0.028). After withdrawal, paroxysmal manifestations recurred with a mean of 24.2 (± 21.9, 52% motor events; p = 0.043). Furthermore, brain energy metabolism normalised with triheptanoin, that is, increased Pi/PCr ratio during brain activation compared to the recovery phase (p = 0.021), and deteriorated when triheptanoin was withdrawn.

CONCLUSIONS

Treatment with triheptanoin resulted in a 90% clinical improvement in non-epileptic paroxysmal manifestations and a normalised brain bioenergetics profile in patients with GLUT1-DS.

TRIAL REGISTRATION NUMBER

NCT02014883.

ADCY5-related dyskinesia: Broader spectrum and genotype-phenotype correlations

OBJECTIVE

To investigate the clinical spectrum and distinguishing features of adenylate cyclase 5 (ADCY5)-related dyskinesia and genotype-phenotype relationship.

METHODS

We analyzed ADCY5 in patients with choreiform or dystonic movements by exome or targeted sequencing. Suspected mosaicism was confirmed by allele-specific amplification. We evaluated clinical features in our 50 new and previously reported cases.

RESULTS

We identified 3 new families and 12 new sporadic cases with ADCY5 mutations. These mutations cause a mixed hyperkinetic disorder that includes dystonia, chorea, and myoclonus, often with facial involvement. The movements are sometimes painful and show episodic worsening on a fluctuating background. Many patients have axial hypotonia. In 2 unrelated families, a p.A726T mutation in the first cytoplasmic domain (C1) causes a relatively mild disorder of prominent facial and hand dystonia and chorea. Mutations p.R418W or p.R418Q in C1, de novo in 13 individuals and inherited in 1, produce a moderate to severe disorder with axial hypotonia, limb hypertonia, paroxysmal nocturnal or diurnal dyskinesia, chorea, myoclonus, and intermittent facial dyskinesia. Somatic mosaicism is usually associated with a less severe phenotype. In one family, a p.M1029K mutation in the C2 domain causes severe dystonia, hypotonia, and chorea. The progenitor, whose childhood-onset episodic movement disorder almost disappeared in adulthood, was mosaic for the mutation.

CONCLUSIONS

ADCY5-related dyskinesia is a childhood-onset disorder with a wide range of hyperkinetic abnormal movements. Genotype-specific correlations and mosaicism play important roles in the phenotypic variability. Recurrent mutations suggest particular functional importance of residues 418 and 726 in disease pathogenesis.

Inherited 1q21.1q21.2 duplication and 16p11.2 deletion: a two-hit case with more severe clinical manifestations

We report paternally inherited duplication of 1q12q21.2 of 5.8 Mb associated with maternally inherited deletion of 16p11.2 of 545 Kb, this latter first identified in a fetus exhibiting an absent nasal bone detected during pregnancy. During the neonatal period, the young boy presented developmental delay, epilepsy, congenital anomalies and overweight. The clinical features of the proband with two rearrangements were more severe than in either of the parents carrying only one or the other mutation. Thus our data support a two-hit model in which the concomitant presence of these two copy-number variations exacerbates the neurodevelopmental phenotype.